1. Field of the Invention
The invention relates to LED airfield lights, like runway lights or taxi-way lights. In particular, the invention relates to a LED airfield light with at least two lighting modules, which are preferably separately replaceable and a method for driving LEDs of the lighting modules.
2. Description of Relevant Art
In the present, LED airfield lights become more and more popular due to their high efficiency and low maintenance costs. Often LED airfield lights comprise two or more separately replaceable lighting modules.
WO99/54854 A2 discloses an airfield lighting system comprising multiple LED airfield lights. These airfield lights each comprise a microprocessor which is connected by a data bus to central control unit. The microprocessor controls the LEDs of the respective airfield light. The microcontroller, the LEDs, switching and control components are integrated in a module, which is separately replaceable.
WO 2009/112318 A1 discloses a lighting device with readable operating parameters. These operating parameters are provided to a controller, which buffers the operating parameters in a separate storage unit. The operating data can be accessed for an external analysis via an interface.
WO 01/45471 A1 discloses an arc lamp. Attached to the arc-lamp is a storage device for storing run time data of the arc lamp. This runtime data can be read by the manufacturer for defending a claim for free replacement, in case the arc-lamp was operated under conditions that did not comply with the arc-lamp's specification.
WO2007/104137A2 discloses a light unit being interchangeably connected to a lighting device with a controller for controlling the activation of one or more lighting elements. The lighting unit has a carrier onto which at least one lighting element and a memory are arranged. In the memory operational characteristics of the lighting element are stored. The controller reads the information from the memory and controls the lighting element according to the information, to thereby avoid a calibration after replacement of a lighting unit of the lighting device.
WO 2007/006684 A1 discloses a LED-traffic light having a light unit for emitting a light signal. The light unit comprises a controller for controlling and driving the LEDs. The controller is connected to a unit, which synchronizes signals being emitted by different light units. To better detect malfunctions of the LEDs the controller of the light unit is positioned in the proximity of the LEDs and not in the unit for synchronizing the signals.
EP 1 696 707 A2 discloses a lighting unit for alighting device. The lighting unit has lighting element, e.g. a LED, and a memory for providing information about the lighting element to a controller via a signaling line. The memory is included in the controller.
EP 1 696 711 A1 discloses a lighting device with a lighting element, a memory and a driver unit. The lighting device is configured for being included a network using the DALI-protocol (DALI means Digital Addressable Lighting Interface). For addressing the lighting devices in the network, a unique identifier of a driver unit of the lighting device is stored in the memory. Additional information, e.g. a type number may be encoded in the unique identifier or stored separately. The type number may be used for retrieving technical data from a data base and to control the lighting device accordingly.
The above summaries of the above referenced prior art include generalizations of the respective technical teachings that are not applicants admitted prior art, by rely on the applicants analysis of the respective documents.